Miguel has been a professor of Administrative Law at Universidad Carlos III de Madrid since 1991, regularly teaching both undergraduate and graduate courses in administrative law subjects.

He has been a visiting professor at the Universities of Bologna, Modena, and Milan (Italy).

Currently (since 2018), he is secretary of the School of Social and Legal Sciences of Universidad Carlos III de Madrid, and he was also Vice-rector of Coordination of Universidad Internacional Menéndez Pelayo (2005–2006).

From 2002–2005 and 2006–2015, Miguel was a lawyer of the Constitutional Court.

He is currently a member of the Academic Council of the Foundation for Research on Law and Business (FIDE), and he has been the secretary of the Spanish Sports Disciplinary Committee (CEDD).

Miguel has directed and is a regular lecturer and speaker at conferences, courses, and seminars in Spain and around the world, and he is a member of the editorial and scientific boards of several leading scientific journals in his field.

He has more than 25 years of experience in forensic defence and in the preparation of legal reports and opinions on matters in his field at the request of public and private institutions. Specialised in Administrative and Constitutional Law, he has defended and advised public administrations, private entities, and individuals in both litigations and constitutional proceedings (petitions for amparo and before the ECHR).